Closure for flexible containers



Feb, 18, 1958 M. M. CUNNINGHAM 2,823,722

CLOSURE FOR FLEXIBLE CONTAINERS Original Filed March 22. 1952 By 29M KM/ ATTORNEY United States Patent 2,823,722 CLOSURE FOR FLEXIBLE CONTAINERS Marlon M; Cunningham, Providence, R. It, assignor to United States Rubber Company, New York, N. Y., a corporation ofNew Jersey Original applicationMarch 22, 1952, Serial No. 277,993,

now Patent No. 2,787,309, dated April 2, 1957. Di- Yided and this application February 14, 1957, Serial No. 640,229

2 Claims. (Cl. 150-8) This invention relates to closures for flexible containerssuch as a flexible drum formed of a plurality of plies of coated fabric.

In my Patent No. 2,559,064 for Fitting for Flexible Containers there'isshown and described a filling and drain fitting that forms a bung hole for a flexible container, and in such patent the fitting cooperates with a reinforcing ring buried in the flexible container wall; The filling fittingof such patent has aninternally threaded metal sleeve provided with an outwardly flaring flange at its lower end adapted to rest against the inner face of the container wall, and engaging this sleeve is a separate flange-ring adapted to be held by the sleeve in clamping engagement with the outer wall of the container. An externally threaded cap is provided as a closure for this fitting. In my copending application Serial No. 277,998, filed March 22, 1952, now Patent No. 2,787,309, of which this application is a division, there is shown a modified filler or drain fitting. The fitting of that application also has an internally threaded metal sleeve.

The present invention contemplates a closure for fittings of these types, and is directed to a closure which is simple to manufacture, and is easy to insert in and remove from the fitting, yet which provides a positive seal against loss of lading from the container. The closure is constructed such that it can easily be rendered tamper proof.

It is contemplated that the closure of the present invention will be used in flexible containers or drums of various sizes, but more particularly for a 55 gallon drum designed to be used in shipping liquids in interstate commerce. Such drums must be strongly constructed and capable of resisting high internal pressures. Therefore the fitting and closure contemplated by the present invention must be made of relatively thick metal and must be clamped very firmly to the flexible walls of the container in order to avoid leakage. The one piece filler fitting contemplated by the present invention is particularly well adapted for use in the above mentioned type of shipping container when the same is to be employed to ship corrosive liquids. When the container is so employed the fitting and the fitting closure are preferably formed of a metal alloy that is highly corrosive resistant.

The closure of this invention comprises a closure cap or plug adapted to be screwed into the threaded fitting and which is provided with a gasket positioned to overlie the line between the closure fitting and plug threaded therein, and having means for tightly clamping this gasket in place to prevent the corrosive contents of the container from escaping around the closure plug.

For a better understanding of the present invention reference should be had to the following description when read in connection with the accompanying drawings, wherein;

Fig. 1 is a side view with parts in section of the upper portion of a flexible container equipped with the closure of the present invention; and

Fig. 2 is a vertical sectional view of the filler fitting erably employed for a reinforced rubber drum such as the cord fabric drum that is described and claimed in Patent 2,612,924. Such a drum, the upper portion of which is shown in. Fig. 1" of the drawing is designated by the numeral 10. This drum preferably is symmetrical in shape and has. opposite convex ends near the outer periphery of the drum, and each end is concaved at its central area; The center end portions are held dished inwardly by the central cable- 11 which is attached to a suitable fitting12- secured to each' end of the container, as more fully set forth in' the above mentioned application; Thisfitting. 12 is: shown ashaving the lifting ring 13 attached thereto;

The present invention, as above stated, relates more particularly to closure 14' cooperating with the filler fitting 14. The fitting 14is preferably mounted at one end of the flexible container as'shown in Fig. l.

The filler fitting 14' shown in the drawing is manufactured in accordance withapplication Serial No. 277,998, and comprises an internally threaded metal sleeve having a lower horizontally. extending flange and an upper flange. The annular space/between these two flanges is adapted to receive the portion of a flexible container wall that surrounds the filler opening cut in the container.

The flexible container 10 is preferably formed of a plurality of plies of cord fabric arranged so that the cords of one ply are disposed at a substantial angle to the next ply. Such cord fabric possesses substantial strength only in a direction in which the cords extend, and if a hole is cut in a container formed of such cord fabric, the walls surrounding such holes are not strong, unless reinforced with some type of metal fitting. In order to increase the strength of the wall structure surrounding such hole a reinforcing ring 18 is preferably buried between the plies of the container wall in surrounding relation with such opening, so that when the fitting 14 is installed it will cooperate with this reinforcing ring 18 to provide a very strong container construction.

The closure 14 of this invention is best shown in Fig. 2 of the drawing and comprises the externally threaded circular plug 26 adapted to be screwed into the sleeve of the filler fitting. This plug is shown as having the inwardly extending boss 27. The plug 26 is also pro vided with the upwardly extending lugs 23 adapted to have a supporting handle or bail 29 secured thereto. The plug 26 is constructed to be screwed into the fitting 14 so that its outer face will be flush with the top of the fitting 14. The plug 26 is provided with a gasket or rubber washer 30 Which is considerably larger in diameter than the plug as shown, and this washer has holes formed therein through which the lugs 28 may extend as shown. The plug 26 has a central hole drilled therein which extends downwardly into the boss 27 and this hole is threaded to receive the clamping bolt 31, the head of which engages a clamping disk 32. The arrangement is such that the plug 14 formed as just described is screwed by hand into the fitting 14 to lie flush with the top of the fitting 14, and then in order to seal the gasket fit) over the threads of the fitting 14 the bolt 31 is tightened to force the metal disk downwardly into tight clamping engagement with the gasket 30. This forms a tight seal that bridges the threaded portion of the fitting to prevent liquid from escaping at the top of the threads. It also makes it very difficult to unscrew the plug to obtain access to the liquid in the container unless the bolt 31 is first backed off. In order to prevent tampering with the contents within the container a sealing wire, not

Patented Feb. 1 8, 1958 shown, may be threaded through holes 33 in the lugs 28 and through a hole 34 in the bolt 31, so that this bolt cannot be turned without breaking the seal.

It will be seen from the foregoing that the present invention provides a highly satisfactory closure plug that cooperates with. the filler fitting so that danger of the liquid being shipped leaking around the fitting cap is effectively guarded against.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. A closure for a container comprising internally threaded means in the container wall forming an opening into the container, externally threaded means adapted to screw into said internally threaded means and to close said opening, a portion of said externally threaded means defining a recess therein having screw threads on the walls defining said recess, a gasket constructed and arranged to cover the juncture between said internally threaded means and said externally threaded means when said externally threaded means is in position to close said opening, a pressure plate adapted to overlie said gasket and exert pressure thereon to force said gasket into sealing engagement with said internally threaded means, externally threaded means constructed to project through said gasket and said pressure plate and to screwinto said recess, and means carried by said latter externally threaded means arranged to force said pressure plate into pressing engagement with said gasket as said externally threaded means is screwed into said recess.

2. A closure fora flexible container, comprising an internally threaded sleeve forming an opening into the container, an externally threaded plug adapted to screw into said internally threaded sleeve and to close said opening, said plug having an internally threaded recess therein, the surface of said plug into which said recess opens having lugs projecting away from said surface, a gasket constructed and arranged to cover the juncture between said internally threaded sleeve and said externally threaded plug when said plug is in position to close the opening in said sleeve, a pressured disk adapted to overlie said gasket and exert pressure thereon at said juncture to force said gasket into sealing engagement with said sleeve and said plug adjacent said juncture, said gasket and said disk having openings therethrough aligned with said recess, said gasket and said disk having openings therethrough aligned with said lugs and through which said lugs are arranged to project, a bail secured to said lugs, and an externally threaded bolt extending through the openings in said disk and said gasket and being threaded in said recess, said bolt being constructed to apply pressure to said disk as said bolt is screwed into said recess. 1

References Cited in the file of this patent UNITED STATES PATENTS 1,340,236 Moehle May 18, 1920 1,588,847 McGee June 15, 1926 2,559,064 Cunningham July 3, 1951 2,612,924 Cunningham Oct. 7, 1952 2,787,309 Cunningham Apr. 2, 1957 

